DEVONIAN FAUNAS. 
ras) 
~ 
Oo 
mens observed have separated, is marked by more or less irregular 
concentric lines, which follow the direction of the lobate distal margin. 
The zocecia are arranged in longitudinal rows, additional rows being 
rarely intercalated, except along the lines dividing the lobes of the 
frond; in tangential section they are seen to be elliptical in outline, 
with their longer axis parallel with the zocecial rows; those in 
adjacent rows are alternate in position, so that they appear, also, to be 
arranged in diagonal lines. The lobation of the zoarium introduces 
some irregularity in the arrangement of the zocecia along the lines 
separating the lobes, the parallel lines of openings in each lobe having 
a different direction, and the openings themselves often being more 
or less oblique. In vertical section the outer portions of the zocecia 
are seen to be at nearly right angles to the mesotheca, the basal portion 
being slightly procumbent; diaphrams are entirely absent, but the 
superior hemisepta are uniformly present. 
Remarks.—As it occurs in the Coeymans limestone in New Jersey, 
split along the mesothecal wall, this species resembles P. frondosa of 
the Decker Ferry formation, but it may always be distinguished from 
that species by its lobed distal margin, and in thin sections by the 
absence of diaphrams. It also resembles P. nebulosa Hall, from the 
Helderbergian of New York, but the internal characters of that species 
have never been described; that species, however, is not described as 
being lobate, and in P. lobata there are no monticules with larger 
zocecia shown in the tangential sections. 
LICHENALIA TORTA Hall. 
Plate XXVI., Figs. 7-8. 
1887. IJnchenalia torta Hall, Pal. N. Y., vol. VL, p. 31, pl. 15, figs. 
1-5, 7. 
Description.—“Zoarium consisting of lamellate expansions, some- 
times flat, at other times more or less involuted or contorted. Under 
surface a thin epitheca, marked by concentric wrinkles and striew, with 
fine, radiating strie. When the celluliferous tissue of the bryozoum 
has been removed, the radiating striz on the upper surface of the 
epitheca are very sharp and prominent, and at their junction with 
the concentric striz form minute nodes. Cell apertures broadly oval 
18 
